Electric switch with improved contact terminal connection means and movable conductive plug contact



g- 1970 c. A. BARNEY ELECTRIC SWITCH WITH IMPROVED CONTACT TERMINAL CONNECTION MEANS AND MOVABLE CDNDUCTIVE PLUG CONTACT Filed June 12, 1969 United States Patent 3,524,028 ELECTRIC SWITCH WITH IMPROVED CONTACT TERMINAL CONNECTION MEANS AND MOV- ABLE CONDUCTIVE PLUG CONTACT Charles A. Barney, Stow, Mass., assignor to Ark-Les Switch Corporation, Watertown, Mass, a corporation of Massachusetts Filed June 12, 1969, Ser. No. 832,643 Int. Cl. H0111 15/04, 1/58 US. Cl. 200-16 10 Claims ABSTRACT OF THE DISCLOSURE A switch comprising a housing having an internal cavity, a slide mounted on the housing and having an insulating plug extending into the cavity, and a resilient conductive element including a base portion, a wire connection portion and a contact portion mounted in the cavity, the wire connection portion being adapted for engaging a wire introduced into the housing and the contact portion being adapted for engaging the plug in a first position and electrically contacting a second conductive element when the plug is in a second position.

This invention relates to switches.

It is a principal object of the present invention to provide a reciprocating or slide switch having no exposed live parts and a greatly simplified construction in which only two metal parts are required both for wire connection and switch operation. Other objects include providing a switch of the type mentioned in which the total number of parts is reduced to a minimum, and each part is of easily and inexpensively manufactured configuration.

The invention features a switch comprising a housing having an internal cavity, a slide mounted on the housing and having an insulating plug extending into the cavity, and a resilient conductive element including a base portion, a wire connection portion and a contact portion mounted in the cavity, the wire connection portion being adapted for engaging a wire introduced into the housing and the contact portion being adapted for engaging the plug in a first position and electrically contacting a second conductive element when the plug is in a second position. In preferred embodiments in which there are two identical resilient elements, each including a wire connection portion and a contact portion connected to a transverse edge of a base portion, there is featured a conductive wiper on the plug for engaging the elements when the plug is in the second position and internal slots in the housing for supporting the base portions of the two elements.

Other objects, features, and advantages will appear from the following detailed description of a preferred embodiment of the invention, taken together with the attached drawings in which:

FIGS. 1 and 2 are perspective views of a switch of the present invention;

FIG. 3 is an exploded perspective view partially in section of the switch of FIG. 1;

FIG. 4 is a perspective sectional view of components of the switch of FIG. 1; and,

FIGS. 5 and 6 are sectional views of the switch of FIG. 1.

Referring more particularly to. the drawings, there is shown a slide switch 10 comprising a generally rectangular casing 12 of insulating material having a large cavity 14 therein in which are housed a pair of identical, spaced contact and wire connection elements 15 and 16. The open top (viewed in FIG. 3) of cavity 14 is covered by an insulating cover plate 18. Plate 18 is located relative to casing 12 by a pair of studs 20 on opposite sides of casing 12 which extend through corresponding slots 22 at the sides of cover plate 18.

A slide 24, also of insulating material, is mounted in an outwardly-facing channel 26 at the bottom of casing 12. Slide 24 includes a rectangular base 28, a plug 30 extending upwardly from base 28 through an elongated rectangular opening 32 in the base of casing 12 into cavity 14, and a finger piece 34 extending downwardly from base 28. A U-shaped copper wiper 36 is mounted on plug 30 within cavity 14.

A light-weight steel mounting plate 38, including a base portion 40 (overlying the bottoms of casing 12 and slide base 28) and two parallel, spaced side portions 42 (extending upwardly from base portion 40), holds slide 24 in place within channel 26 and secures cover plate 18 to casing 12. Base portion 40 includes an elongated rectangular slot or opening 44 through which finger piece 34 extends and a pair of mounting holes 46. Each side portion 42 includes two retaining fingers 48 which extend upwardly from the top edge of the side portion through corresponding slots 51 in an edge of cover plate 18 and are then bent over the top of the cover plate.

Contact and wire connection elements 15 and 16 are identical. As shown most clearly in FIG. 3, each element is constructed of a single piece of resilient bronze and includes a base portion 50, a wire connection portion 52 and a contact portion 54. Wire connection portion 52 is flat and extends outwardly from a transverse edge of base portion 50 coplanar therewith. The transverse edge 56 of wire connection portion 52 most distant from base portion 50 is concave. Contact portion extends outwardly from the same transverse edge of base portion 50 as does wire connection portion 52 and includes an initial segment coplanar with and connected to base portion 50, an intermediate planar segment forming an acute angle with base portion 50, and an inwardly convex contact segment 58 forming a larger angle with base portion 50.

Each element is mounted within cavity 14 adjacent and forming an acute angle with an end wall thereof with its transverse edge 56 engaging one of the side walls of the cavity and its contact segment 50 overlying and spaced slightly from that side wall. Elements 15 and 16 are mounted within cavity 14 in an identical manner and only the mounting of element 16 will be described in detail.

Referring now to FIGS. 3 and 4, a pair of shoulders 62, 64 cooperate to define a vertical slot, extending angularly into cavity 14 from adjacent the intersection of end wall 60 and side wall 70, in which base portion 50 of element 16 is placed. Shoulder 62 juts inwardly from end wall 60 and extends upwardly from the bottom of cavity 14 to the lower edge of an opening 72 which extends through the upper portion of end wall :60 adjacent side wall 68. Shoulder 64, jutting inwardly from side wall 70, extends upwardly from the bottom of cavity 14 a distance equal to the width of contact portion 54. A third shoulder 66 juts inwardly from side wall 68 of cavity 14, is spaced from end wall 60, and engages wire connection portion 52 adjacent concave transverse edge 56 thereof.

An opening 73, similar to opening 72 extends through the upper portion of end wall 61 adjacent side wall 68. Shoulders '63, 65 and 67, similar respectively to shoulders 62, 64 and 66, are disposed within cavity 14 adjacent end wall 61.

As shown, each of openings 72, 73 includes a full depth wire insertion portion (whose lower edge is slightly above the lower edge of wire connection portion 52) and a partial depth wire release portion (about one-half as deep as the wire insertion portion and through which a release probe may be introduced into cavity 14 for bending wire connection portion 52 to release a wire engaged thereby).

In operation, the stripped ends of insulated wires 82 are inserted into switch 10 through the wire connection portions of openings 72 and 73. As shown in FIG. 5, each end 80 is inserted between the shoulder 66 adjacent the opening and the transverse edge 56 of the wire connection portion 52 engaging the shoulder. As previously mentioned, such wire connection portion 52 is inclined relative to the end wall of base 12 so that it will flex inwardly as the wire is inserted and be drawn tightly against the stripped end 80 if the wire is drawn in the other direction.

With wires 82 inserted in place, as shown in FIG. 5, all live switch components are within the bounds of base '12.

Reference is now made to FIGS. and 6 wherein switch 10 is shown, respectively, in its off and on positions. As there illustrated, slide 24 is movable longitudinally relative to base 12 between the off position, shown in FIG. 5 wherein contact portions 58 of elements 15, 16 engage electrically insulating portions of plug 30, and the on position, shown in FIG. 6, wherein contact portions 58 engage (and are electrically connected by) wiper 36. The longitudinal movement of slide 24 is limited by the length of opening 32 in the base of casing 12. In the oif position, an end 23 of plug 30 is flush against one transverse edge 31 of opening 32; in the on position the other end 25 of plug 30 is flush against the other transverse edge 33 of opening 32. The portion of plug 30 intermediate wiper 36 and the plug portion engaged by contact portions 58 when the switch is off is of increased thickness to insure positive switching action.

Other embodiments within the scope of the following claims will occur to those skilled in the art.

What is claimed is:

1. A slide switch comprising:

a housing having a cavity therein, said housing defining a wire connection opening extending through a wall thereof;

a slide mounted on said housing for movement relative thereto and including an insulating plug extending into said cavity;

a resilient conductive element mounted within said cavity;

said element including a base section secured in position within said housing and wire connection and contact sections extending outwardly from an edge of said base section for flexure relative thereto,

said wire connection section overlying said opening and having a free edge adjacentan interior wall of said housing whereby a wire may be introduced into said cavity through said opening and inserted intermediate and engaged by said free edge and said interior wall, and

a portion of said contact section being disposed on one side of said plug; and

a second conductive element disposed on the other side of said plug,

said plug being movable between and relative to said portion and said second element between a first position wherein said portion and said second element are electrically insulated from each other and said portion engages said plug and a second position wherein said portion and said second element are electrically connected.

2. The switch of claim 1 wherein said base section, said wire connection section and portions of said contact section are planar.

3. The switch of claim 2 wherein said base section and said wire connection section are coplanar.

4. The switch of claim 1 wherein said second conductive element is substantially identical to said resilient conductive element.

5. The switch of claim 4 including a conductive Wiper mounted on said plug in position for engaging said elements when said plug is in said second position.

6. The switch of claim 1 wherein said housing defines a wire connection opening extending through each of a pair of opposite walls thereof, an edge of each of said openings is aligned with an interior Wall of said cavity, and including a pair of substantially identical resilient conductive elements, each of said elements including a wire connection section overlying one of said openings and having a free edge adjacent the inner wall of said cavity aligned with said one opening.

7. The switch of claim 6 wherein the base section of each of said elements is supported in a slot defined by References Cited UNITED STATES PATENTS 2,441,888 5/1948 Lansing 200-16 2,45 3,23 1 ll/ 1948 Kavanagh 2001 6 3,296,389 1/1967 Hults 200-16 3,315,062 4/1967 Mo Goto.

ROBERT K. SCHAEFER, Primary Examiner J. R. SCOTT, Assistant Examiner Us. 01. X.R. 200'-166 

